Air supply device using pressurization to store hydrogen and air supply system

The invention provides an air compression device comprising a cylinder, which is provided with a hydrogen chamber and an air chamber separated by a separation band; a piston, which can move with respect to the separation band; a hydrogen suck-in part, which is used for supplying the hydrogen chamber with the hydrogen; a hydrogen exhaust part, which is used for exhausting the hydrogen in the hydrogen chamber; an air suck-in part, which is used for supplying the air chamber with the air; and an air exhaust part, which is used for exhausting the air in the air chamber. According to the invention, no extra motor and impeller are adopted, and the decompressor can be used for the decompression of the compressed hydrogen, and therefore the lightweight of the products, the simplification of the engineering, and the energy efficiency can be improved. The stability of the products and the environment can be improved, because there are no noises and vibration caused by the motor and the impeller.